This invention relates to latches or catches for cabinets and the like.
The invention relates particularly to a catch of the "push-to-open" type. This type is also sometimes referred to as the "invisible" type, since no hardware is mounted on the outside surface of the cabinet or other closure to which the catch is applied.
Prior art catches of the "push-to-open" or "invisible" types have included both mechanical and magnetic catches. However, the mechanical catches of this type have been subject to jamming and/or failure to close due to minor misalignment. And, if a mechanical catch of this type fails to release, it cannot be repaired or replaced without damaging the cabinet to remove the catch.
Magnetic catches have the advantage that if a component should break, or the catch should jam, the door can be opened without damaging or destroying the door. The prior art magnetic catches of the "push-to-open" type have included complicated mechanisms to reduce the magnetic field by moving the pole pieces with respect to the magnet. A magnetic catch of this type is described in Hutchinson U.S. Pat. No. 3,492,037. However, the Hutchinson magnetic catch has a disadvantage in that the catch is subject to over-travel when being fastened, in which case the door may be inadvertently released.
A magnetic catch of the "push-to-open" type is also shown in Teetor U.S. Pat. No. 2,673,111. However, the Teetor magnetic catch operates in only one position with respect to gravity, so that it may be mounted only on a vertical door jam. Moreover, after opening the door, the magnetic catch is not always fully returned to the position where it may contact the door upon its next closing. These are two disadvantages of the Teetor catch.